LSM may refer to: Lanthanum strontium manganite, a crystal used as a cathode material. LSm, a family of RNA-binding proteins. LSM-775, a psychedelic drug similar to LSD, although less potent. Modane Underground Laboratory (Laboratoire Souterrain de Modane), a particle physics laboratory in France.
Landing Ship Medium were amphibious assault ships of the United States Navy in the World War II. Of comparable size to Landing Ship, Tank and the Landing Craft, Infantry, there were 558 LSM (Landing Ship, Medium) made for the USN between 1944 and 1945.
In computer science, the log-structured merge-tree (or LSM tree) is a data structure with performance characteristics that make it attractive for providing indexed access to files with high insert volume, such as transactional log data. LSM trees, like other search trees, maintain key-value pairs.